We could just collect a bunch of data. For a material .What's the volume it occupies at some pressure and temperature?

对一种物质我们可以得到一系列测量数据,在给定的温度和气压下,它的体积是什么？

麻省理工公开课 - 热力学与动力学课程节选

It would be much better if you had a reference point that didn't care where the pressure was.

我们还需要精确地定义气压,你必须知道气压的大小,当然如果我们能找到一个。

麻省理工公开课 - 热力学与动力学课程节选

Now let's change the pressure and temperature and sweep through a whole range of pressures and temperatures and measure the volume in every one of them.

然后改变气压和温度,并且让气压和温度,取便所有可能的数值,测量相应的体积。

麻省理工公开课 - 热力学与动力学课程节选

There's hardly any vapor pressure above your ice water glass.

冰水混合物上方,水蒸气的气压非常小。

麻省理工公开课 - 热力学与动力学课程节选